landbeforetimefandomcom-20200216-history
Parasaurolophus
Parasaurolophus (pronounced /ˌpærəsɔˈrɒləfəs/ PARR-ə-saw-ROL-ə-fəs, commonly also /ˌpærəˌsɔrəˈloʊfəs/ PARR-ə-SAWR-ə-LOH-fəs; meaning "near crested lizard" in reference to Saurolophus) is a genus of ornithopod dinosaur from the Late Cretaceous Period of what is now North America, about 76-73 million years ago. It was a herbivore that walked both as a biped and a quadruped. Three species are recognized: P. walkeri (the type species), P. tubicen, and the short-crested P. cyrtocristatus. Remains are known from Alberta, Canada, and New Mexico and Utah, USA. It was first described in 1922 by William Parks from a skull and partial skeleton in Alberta. Parasaurolophus is a hadrosaurid, part of a diverse family of Cretaceous dinosaurs known for their range of bizarre head adornments. This genus is known for its large, elaborate cranial crest, which at its largest forms a long curved tube projecting upwards and back from the skull. Charonosaurus from China, which may have been its closest relative, had a similar skull and potentially a similar crest. The crest has been much discussed by scientists; the consensus is that major functions included visual recognition of both species and sex, acoustic resonance, and thermoregulation. It is one of the rarer duckbills, being known from only a handful of good specimens. Parasaurolophus is among the most well-recognized dinosaurs, and is frequently portrayed in dinosaur-related television shows, movies, books, merchandise and other media. In the Land Before Time series, there are many Parasaurolophus characters featured, most notably the main character Ducky and her family (excluding Spike, her adopted Stegosaurus brother). Description As is the case with most dinosaurs, the skeleton of Parasaurolophus is incompletely known. The length of the type specimen of P. walkeri is estimated at 9.5 meters (31 ft). Its skull is about 1.6 meters (5.2 ft) long, including the crest, whereas the type skull of P. tubicen is over 2.0 meters (6.6 ft) long, indicating a larger animal.Lull, Richard Swann Wright, Nelda E. Hadrosaurian Dinosaurs of North America, page 229. Published: 1942, Geological Society of America, Geological Society of America Special Paper '''40' Its weight is estimated at 2.5 tonnes (2.7 tons).Glut, Donald F. Dinosaurs: The Encyclopedia, Chapter: ''Parasaurolophus, pages 678–684. Published: 1997, McFarland & Co, in Jefferson, North Carolina. ISBN 0-89950-917-7 Its single known forelimb was relatively short for a hadrosaurid, with a short but wide shoulder blade. The thighbone measures 103 centimeters (3.38 ft) long in P. walkeri and is robust for its length when compared to other hadrosaurids.Lull and Wright, Hadrosaurian Dinosaurs of North America, pp. 209-213. The upper arm and pelvic bones were also heavily built.Brett-Surman, Michael K. and Wagner, Jonathan R. Carpenter, Kenneth (ed.) Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs, chapter: Appendicular anatomy in Campanian and Maastrichtian North American hadrosaurids, pages 135–169. Published, 2006, Indiana University Press, in Bloomington and Indianapolis ISBN 0-253-34817-X Like other hadrosaurids, it was able to walk on either two legs or four. It probably preferred to forage for food on four legs, but ran on two.Horner, John R., Weishampel, David B.; and Forster, Catherine A, Weishampel, David B.; Osmólska, Halszka; and Dodson, Peter (eds.) The Dinosauria, 2nd edition, chapter: Hadrosauridae, pages 438-463. Published: 2004, University of California Press, in Berkeley. ISBN 0-520-24209-2 The neural spines of the vertebrae were tall, as was common in lambeosaurines; tallest over the hips, they increased the height of the back. Skin impressions are known for P. walkeri, showing uniform tubercle-like scales but no larger structures.Parks, William A. Parasaurolophus walkeri, a new genus and species of crested trachodont dinosaur, volume 13, pages 1-32. Published: 1922, University of Toronto Studies, Geology Series. The most noticeable feature was the cranial crest, which protruded from the rear of the head and was made up of the premaxilla and nasal bones. The P. walkeri type specimen has a notch in the neural spines near where the crest would hit the back, but this may be a pathology peculiar to this individual. William Parks, who named the genus, hypothesized that a ligament ran from the crest to the notch to support the head. Although the idea seems unlikely, Parasaurolophus is sometimes restored with a skin flap from the crest to the neck. The crest was hollow, with distinct tubes leading from each nostril to the end of the crest before reversing direction and heading back down the crest and into the skull. The tubes were simplest in P. walkeri, and more complex in P. tubicen, where some tubes were blind and others met and separated.Sullivan, Robert M. and Williamson, Thomas E. A new skull of Parasaurolophus (Dinosauria: Hadrosauridae) from the Kirtland Formation of New Mexico and a revision of the genus, from the series New Mexico Museum of Natural History and Science Bulletin, 15, pages 1-52. Published: 1999, New Mexico Museum of Natural History and Science, in Albuqueque, New Mexico. While P. walkeri and P. tubicen had long crests with only slight curvature, P. cyrtocristatus had a short crest with a more circular profile.Ostrom, John H. 1961 A new species of hadrosaurian dinosaur from the Cretaceous of New Mexico, Journal of Paleontology, Volume 35, 3rd issue, on pages 575–577. Classification As its name implies, Parasaurolophus was initially thought to be closely related to Saurolophus because of its superficially similar crest. However, it was soon reassessed as a member of the lambeosaurine subfamily of hadrosaurids—''Saurolophus'' is an hadrosaurine.Gilmore, Charles W., On the genus Stephanosaurus, with a description of the type specimen of Lambeosaurus lambei, volume 38, issue 43, pages 29-48, Parks. Published: 1924, Canada Department of Mines Geological Survey Bulletin (Geological Series) It is usually interpreted as a separate offshoot of the lambeosaurines, distinct from the helmet-crested Corythosaurus, Hypacrosaurus, and Lambeosaurus.Weishampel, David B. and Horner, Jack R., Weishampel, David B.; Osmólska, Halszka; and Dodson, Peter (eds.) The Dinosauria, 1st edition, Chapter: Hadrosauridae, pages 534-561. Published: 1990, University of California Press in Berkeley. ISBN 0-520-06727-4Evans, David C., and Reisz, Robert R. 2007. Anatomy and relationships of Lambeosaurus magnicristatus, a crested hadrosaurid dinosaur (Ornithischia) from the Dinosaur Park Formation, Alberta, from the Journal of Vertebrate Paleontology, vol. 27 issue 2, on pages 373–393. url=http://www.vertpaleo.org/publications/jvp/27-373-393.cfm Its closest known relative appears to be Charonosaurus, a lambeosaurine with a similar skull (but no complete crest yet) from the Amur region of northeastern China,Godefroit, Pascal, Shuqin Zan; and Liyong Jin. 2000. Charonosaurus jiayinensis n. g., n. sp., a lambeosaurine dinosaur from the Late Maastrichtian of northeastern China, from the Compte Rendus de l'Academie des Sciences, Paris, Sciences de la Terre et des planètes, vol. 330, pages 875–882. and the two may form a clade Parasaurolophini. P. cyrtocristatus, with its short, rounder crest, may be the most basal of the three known Parasaurolophus species, or it may represent subadult or female specimens of P. tubicen.Williamson, Thomas E. 2000. Review of Hadrosauridae (Dinosauria, Ornithischia) from the San Juan Basin, New Mexico Lucas, S.G.; and Heckert, A.B. (eds.) Dinosaurs of New Mexico, from the New Mexico Museum of Natural History and Science Bulletin, 17 Published by New Mexico Museum of Natural History and Science, in Albuqueque, New Mexico. Pages 191–213. History Dicovery and naming ]] Meaning "near crested lizard", the name Parasaurolophus is derived from the Greek para/παρα "beside" or "near", saurus/σαυρος "lizard" and lophos/λοφος "crest".Liddell, Henry George and Robert Scott, 1980. A Greek-English Lexicon (Abridged Edition) Published: Oxford University Press in the United Kingdom. ISBN 0-19-910207-4 It is based on ROM 768, a skull and partial skeleton missing most of the tail and the hind legs below the knees, which was found by a field party from the University of Toronto in 1920 near Sand Creek along the Red Deer River in Alberta, Canada. These rocks are now known as the Campanian-age Upper Cretaceous Dinosaur Park Formation. William Parks named the specimen P. walkeri in honor of Sir Byron Edmund Walker, Chairman of the Board of Trustees of the Royal Ontario Museum. Parasaurolophus remains are rare in Alberta,Ryan, Michael J. and Evans, David C., Currie, Phillip J., and Koppelhus, Eva (eds.). Dinosaur Provincial Park: A Spectacular Ancient Ecosystem Revealed, Chapter: Ornithischian Dinosaurs. 2005, Published: Indiana University Press, in Bloomington. Pages 312–348, ISBN 0-253-34595-2 with only one other partial skull from (probably) the Dinosaur Park Formation,Evans, David C., Reisz, Robert R.; and Dupuis, Kevin, 2007. A juvenile Parasaurolophus braincase from Dinosaur Provincial Park, Alberta, with comments on crest ontogeny in the genus. Journal of Vertebrate Paleontology, vol. 27, issue 3 pages 642–650. and three Dinosaur Park specimens lacking skulls, possibly belonging to the genus.Currie, Phillip J; and Russell, Dale A. "Geographic and stratigraphic distribution of dinosaur remains" in Dinosaur Provincial Park, p. 553. In some faunal lists, there is a mention of possible P. walkeri material in the Hell Creek Formation of Montana, a rock unit of late Maastrichtian age.Weishampel, David B. (1990). "Dinosaur Distribution", in The Dinosauria (1st), pp. 63–139.Weishampel, David B.; Barrett, Paul M.; Coria, Rodolfo A.; Le Loeuff, Jean; Xu Xing; Zhao Xijin; Sahni, Ashok; Gomani, Elizabeth, M.P.; and Noto, Christopher R. (2004). "Dinosaur Distribution", in The Dinosauria (2nd), pp. 517–606. This occurrence is not noted by Sullivan and Williamson in their 1999 review of the genus, and has not been further elaborated upon elsewhere. In 1921, Charles H. Sternberg recovered a partial skull (PMU.R1250) from what is now known as the slightly younger Kirtland Formation in San Juan County, New Mexico. This specimen was sent to Uppsala, Sweden, where Carl Wiman described it as a second species, P. tubicen, in 1931.Wiman, Carl, 1931. Parasaurolophus tubicen, n. sp. aus der Kreide in New Mexico, from the Nova Acta Regia Societas Scientarum Upsaliensis, series 4, vol. 7, issue 5. (German). Pages 1–11. The specific epithet is derived from the Latin tǔbǐcěn "trumpeter". A second, nearly complete P. tubicen skull (NMMNH P-25100) was found in New Mexico in 1995. Using computed tomography of this skull, Robert Sullivan and Thomas Williamson gave the genus a monographic treatment in 1999, covering aspects of its anatomy and taxonomy, and the functions of its crest. Williamson later published an independent review of the remains, disagreeing with the taxonomic conclusions. John Ostrom described another good specimen (FMNH P27393) from New Mexico as P. cyrtocristatus in 1961. It includes a partial skull with a short, rounded crest, and much of the postcranial skeleton except for the feet, neck, and parts of the tail. Its specific name is derived from the Latin curtus "shortened" and cristatus "crested".Simpson, D.P. Cassell's Latin Dictionary, published by Cassell Ltd. 1979, edition 5, in London. ISBN 0-304-52257-0 Page 883. The specimen was found in either the top of the Fruitland Formation or, more likely, the base of the overlying Kirtland Formation. The range of this species was expanded in 1979, when David B. Weishampel and James A. Jensen described a partial skull with a similar crest (BYU 2467) from the Campanian-age Kaiparowits Formation of Garfield County, Utah.Weishampel, David B. and Jensen, James A. 1979. Parasaurolophus (Reptilia: Hadrosauridae) from Utah, from the Journal of Paleontology, vol. 53, issue 6, pages 1422–1427. Since then, another skull has been found in Utah with the short/round P. cyrtocristatus crest morphology. Species , London.]] The type species P. walkeri, from Alberta, is known from a single specimen. It differs from P. tubicen by having simpler tubes in its crest, and from P. cyrtocristatus by having a long, unrounded crest and a longer upper arm than forearm. P. tubicen, from New Mexico, is known from the remains of at least three individuals. It is the largest species, with more complex air passages in its crest than P. walkeri, and a longer, straighter crest than P. cyrtocristatus. P. cyrtocristatus, from New Mexico and Utah, is known from three possible specimens. It is the smallest species, with a short rounded crest. Its small size and the form of its crest have led several scientists to suggest that it represents juveniles or females of P. tubicen, which is from roughly the same time and from the same formation in New Mexico. As noted by Thomas Williamson, the type material of P. cyrtocristatus is about 72% the size of P. tubicen, close to the size at which other lambeosaurines are interpreted to begin showing definitive sexual dimorphism in their crests (~70% of adult size). This position has been rejected in recent reviews of lambeosaurines. Paleobiology Paleoecology '' (left) attacking a Parasaurolophus cyrtocristatus.]] Parasaurolophus walkeri, from the Dinosaur Park Formation, was a member of a diverse and well-documented fauna of prehistoric animals, including well-known dinosaurs such as the horned Centrosaurus, Styracosaurus, and Chasmosaurus; fellow duckbills Prosaurolophus, Gryposaurus, Corythosaurus, and Lambeosaurus; tyrannosaurid Gorgosaurus; and armored Edmontonia and Euoplocephalus. It was a rare constituent of this fauna. The Dinosaur Park Formation is interpreted as a low-relief setting of rivers and floodplains that became more swampy and influenced by marine conditions over time as the Western Interior Seaway transgressed westward.Eberth, David A. 2005. "The geology", in Dinosaur Provincial Park, pp. 54-82. The climate was warmer than present-day Alberta, without frost, but with wetter and drier seasons. Conifers were apparently the dominant canopy plants, with an understory of ferns, tree ferns, and angiosperms.Braman, Dennis R., and Koppelhus, Eva B. 2005. "Campanian palynomorphs", in Dinosaur Provincial Park, pp. 101-130. The New Mexican species shared their environment with the large sauropod Alamosaurus, duckbill Kritosaurus, horned Pentaceratops, armored Nodocephalosaurus, Saurornitholestes, and currently unnamed tyrannosaurids. The Kirtland Formation is interpreted as river floodplains appearing after a retreat of the Western Interior Seaway. Conifers were the dominant plants, and chasmosaurine horned dinosaurs were apparently more common than hadrosaurids.Russell, Dale A. An Odyssey in Time: Dinosaurs of North America, 1989. Publisher: NorthWord Press, in Minocqua, Wisconsin. ISBN 1-55971-038-1 Pages 160–164. Feeding As a hadrosaurid, Parasaurolophus was a large bipedal/quadrupedal herbivore, eating plants with a sophisticated skull that permitted a grinding motion analogous to chewing. Its teeth were continually replacing and packed into dental batteries that contained hundreds of teeth, only a relative handful of which were in use at any time. It used its beak to crop plant material, which was held in the jaws by a cheek-like organ. Feeding would have been from the ground up to around 4 meters (13 ft) above. As noted by Bob Bakker, lambeosaurines have narrower beaks than hadrosaurines, implying that Parasaurolophus and its relatives could feed more selectively than their broad-beaked, crestless counterparts.Bakker, Robert T. 1986. The Dinosaur Heresies: New Theories Unlocking the Mystery of the Dinosaurs and their Extinction, published by William Morrow, in New York. ISBN 0-8217-2859-8 Page 194. Cranial crest Many hypotheses have been advanced as to what functions the cranial crest of Parasaurolophus performed, but most have been discredited.Norman David B. The Illustrated Encyclopedia of Dinosaurs: An Original and Compelling Insight into Life in the Dinosaur Kingdom, chapter: Hadrosaurids II. 1985. Published by Crescent Books, in New York. Pages 122–127. ISBN 0-517-468905 It is now believed that it may have had several functions: visual display for identifying species and sex, sound amplification for communication, and thermoregulation. It is not clear which was most significant at what times in the evolution of the crest and its internal nasal passages. Differences between species and growth stages As for other lambeosaurines, it is believed that the cranial crest of Parasaurolophus changed with age and was a sexually dimorphic characteristic in adults. James Hopson, one of the first researchers to describe lambeosaurine crests in terms of such distinctions, suggested that P. cyrtocristatus, with its small crest, was the female form of P. tubicen.Hopson, James A. 1975. The evolution of cranial display structures in hadrosaurian dinosaurs , from the Journal of Paleobiology, volume one, issue one, pages 21–43. Thomas Williamson suggested it was the juvenile form. Neither hypothesis became widely accepted. As only six good skulls and one juvenile braincase are known, additional material will help clear up these potential relationships. Williamson noted that in any case, juvenile Parasaurolophus probably had small, rounded crests like P. cyrtocristatus, that probably grew faster as individuals approached maturity. Recent restudy of a juvenile braincase previously assigned to Lambeosaurus, and now assigned to Parasaurolophus, provides evidence that a small tubular crest was present in juveniles. This specimen preserves a small upward flaring of the frontal bones that was similar to but smaller than what is seen in adult specimens; in adults, the frontals formed a platform that supported the base of the crest. This specimen also indicates that the growth of the crest in Parasaurolophus and the facial profile of juvenile individuals differed from the Corythosaurus-''Hypacrosaurus''-''Lambeosaurus'' model, in part because the crest of Parasaurolophus lacks the thin bony 'coxcomb' that makes up the upper portion of the crest of the other three lambeosaurines. Rejected hypotheses about function Many early suggestions focused on adaptations for an aquatic lifestyle, following the hypothesis that hadrosaurids were amphibious, a common line of thought until the 1960s. Thus, Alfred Sherwood Romer proposed it served as a snorkel,Romer. Alfred Sherwood, 1933. Vertebrate Paleontology, from the University of Chicago Press, on page 491. Martin Wilfarth that it was an attachment for a mobile proboscis used as a breathing tube or for food gathering,Wilfarth, Martin, 1947. Russeltragende Dinosaurier, from the Journal of Orion (Munich), vol. 2. pp. 525–532 (German language). Charles M. Sternberg that it served as an airtrap to keep water out of the lungs,Sternberg, Charles M. 1935. Hooded hadrosaurs of the Belly River Series of the Upper Cretaceous from the Journal of the Canada Department of Mines Bulletin (Geological Series), volume 77, issue 52, on pages 1–37. and Ned Colbert that it served as an air reservoir for prolonged stays underwater.Colbert, Edwin H. The Dinosaur Book: The Ruling Reptiles and their Relatives, published in 1945 by the American Museum of Natural History, Man and Nature Publications, 14, in New York. Page 156. Other proposals were more physical in nature. As mentioned above, William Parks suggested that it was joined to the vertebrae with ligaments or muscles, and helped with moving and supporting the head. Othenio Abel proposed it was used as a weapon in combat among members of the same species,Abel, Othenio, 1924. Die neuen Dinosaurierfunde in der Oberkreide Canadas from the Journal of Jarbuch Naturwissenschaften, volume 12, issue 36, on pages 709–716. (German) 1924. and Andrew Milner suggested that it could be used as a foliage deflector, like the helmet crest (called a 'casque') of the cassowary. Still other proposals made housing specialized organs the major function. Halszka Osmólska suggested that it housed salt glands,Osmólska, Halszka, 1979. Nasal salt glands in dinosaurs, from the Journal of Acta Palaeontologica Polonica, vol. 24, pages 205–215. and John Ostrom suggested that it housed expanded areas for olfactory tissue and much improved sense of smell of the lambeosaurines, which had no obvious defensive capabilities.Ostrom, John H., 1962. The cranial crests of hadrosaurian dinosaurs, from the Journal of Postilla, vol. 62, pages 1–29. One unusual suggestion, made by creationist Duane Gish, is that the crest housed chemical glands that allowed it to throw jets of chemical "fire" at enemies, similar to the modern-day bombardier beetle.Gish, Duane T., 1992. Dinosaurs by Design, published by Master Books, in Green Forest. ISBN 0-89051-165-9 Page 82. Most of these hypotheses have been discredited or rejected. For example, there is no hole at the end of the crest for a snorkeling function. There are no muscle scars for a proboscis and it is dubious that an animal with a beak would need one. As a proposed airlock, it would not have kept out water. The proposed air reservoir would have been insufficient for an animal the size of Parasaurolophus. Other hadrosaurids had large heads without needing large hollow crests to serve as attachment points for supporting ligaments. Also, none of the proposals explain why the crest has such a shape, why other lambeosaurines should have crests that look much different but perform a similar function, how crestless or solid-crested hadrosaurids got along without such capabilities, or why some hadrosaurids had solid crests. These considerations particularly impact hypotheses based on increasing the capabilities of systems already present in the animal, such as the salt gland and olfaction hypotheses, and indicate that these were not primary functions of the crest. Additionally, work on the nasal cavity of lambeosaurines shows that olfactory nerves and corresponding sensory tissue were largely outside the portion of the nasal passages in the crest, so the expansion of the crest had little to do with the sense of smell.Evans, David C., 2006. Nasal cavity homologies and cranial crest function in lambeosaurine dinosaurs, from the Journal of Paleobiology, vol. 32, issue 1, Pages 109–125. http://findarticles.com/p/articles/mi_qa4067/is_200601/ai_n17169984 Sounding function However, the external appearance of the crest does not correspond to the complex internal anatomy of the nasal passages, which suggests another function accounted for usage of the internal space. Carl Wiman was the first to propose, in 1931, that the passages served an auditory signaling function, like a crumhorn; Hopson and David B. Weishampel revisited this idea in the 1970s and 1980s.Weishampel, David B., 1981. Acoustic analyses of potential vocalization in lambeosaurine dinosaurs (Reptilia:Ornithischia), from the Journal of Paleobiology, vol. 7, issue 2, pp. 252–261.Weishampel David B., 1981. The nasal cavity of lambeosaurine hadrosaurids (Reptilia:Ornithischia): comparative anatomy and homologies, from the Journal of Paleontology, vol. 55, issue 5, pp. 1046–1057. Hopson found that there is anatomical evidence that hadrosaurids had strong hearing. There is at least one example, in the related Corythosaurus, of a slender stapes (reptilian ear bone) in place, which combined with a large space for an eardrum implies a sensitive middle ear. Furthermore, the hadrosaurid lagena is elongate like a crocodilian's, indicating that the auditory portion of the inner ear was well-developed. Weishampel suggested that P. walkeri was able to produce frequencies of 48 to 240 Hz, and P. cyrtocristatus (interpreted as a juvenile crest form) 75 to 375 Hz. Based on similarity of hadrosaurid inner ears to those of crocodiles, he also proposed that adult hadrosaurids were sensitive to high frequencies, such as their offspring might produce. According to Weishampel, this is consistent with parents and offspring communicating. Computer modeling of a well-preserved specimen of P. tubicen, with more complex air passages than those of P. walkeri, has allowed the reconstruction of the possible sound its crest produced.[http://www.sandia.gov/media/dinosaur.htm Scientists Use Digital Paleontology to Produce Voice of Parasaurolophus Dinosaur,] by the Sandia National Laboratories (1997-12-05). Retrieved on January 20th, 2009. The main path resonates at around 30 Hz, but the complicated sinus anatomy causes peaks and valleys in the sound.Diegert, Carl F. and Williamson, Thomas E., 1998. A digital acoustic model of the lambeosaurine hadrosaur Parasaurolophus tubicen from the Journal of Vertebrate Paleontology, vol. 18, issue 3, Suppl. p. 38A. Cooling function The large surface area and vascularization of the crest also suggests a thermoregulatory function.Sullivan, Robert M. and Williamson, Thomas E., 1996. A new skull of Parasaurolophus (long-crested form) from New Mexico: external and internal (CT scans) features and their functional implications, from the Journal of Vertebrate Paleontology, vol. 16, issue 3, Suppl. pp.68A. P.E. Wheeler first suggested this use in 1978 as a way keep the brain cool.Wheeler, P.E., 1978. Elaborate CNS cooling structure in large dinosaurs Journal of Nature, vol. 275, on pp. 441–443. Teresa Maryańska and Osmólska also proposed thermoregulation at about the same time,Maryańska, Teresa and Osmólska, Halszka, in 1979. Aspects of hadrosaurian cranial anatomy, from the Journal of Lethaia, vol. 12, on pp. 265–273. and Sullivan and Williamson took further interest. David Evans' 2006 discussion of lambeosaurine crest functions was favorable to the idea, at least as an initial factor for the evolution of crest expansion. Parasaurolophus, in The Land Before Time Parasaurolophus is a very prominently-featured genus in ''The Land Before Time'' films and television series. The characters in the series use a number of terms to describe the species, including "Duck-bill" (which is in fact a real-world slang term associated with many hadrosaurid dinosaurs), "swimmer" (due to the characters' abilities to swim) and "big mouth". The main character Ducky, her parents, and her biological siblings are all identified as Parasaurolophus on the official Land Before Time website,Official Land Before Time website. although there is much persistence from the fans of the series that the characters are more congruent in appearance to Saurolophus,Revision history of Ducky's Wikipedia article; specifically edits in which users call her a Saurolophus instead of a Parasaurolophus. (November 14th, 2006) (January 5th, 2007) (February 26th, 2007) (May 22nd, 2007) (July 13th, 2007) (August 26th, 2007.) (25th September, 2007.) Originally retrieved on April 17th/18th, 2008.Revision history of The Land Before Time's Wikipedia article; specifically edits in which users call her a Saurolophus instead of a Parasaurolophus. (September 28th, 2008) (August 10th, 2005) Originally retrieved on November 28th, 2008. due to the shortness of their crests, and reviewers of the series frequently mistake them to be Anatosaurus (which is officially Edmontosaurus).Mary Kalin-Casey review on The Big Freeze''Joe Leydon's review of ''Journey Through the Mists''British journalist MJ Simpson's review of ''The Land Before Time II: The Great Valley Adventure, on his official website. Retrieved on December 4th, 2008.The Animated Movie Guide by Jerry Beck. Published 2005, Chicago Review Press. ISBN 1556525915 Page 138.From Abba to Zoom: A Pop Culture Encyclopedia of the Late 20th Century by David Mansour. Published 2005 Andrews McMeel Publishing. ISBN 0740751182 Page 272. However, they have apparently failed to note that Parasaurolophus cirtocrystatus had a much shorter crest that P. walkeri and P. tubicen, and also that Edmontosaurus (Anatosaurus) lacked any head crest, as far as has been discovered. Many other Parasaurolophus characters, mostly being closer in resemblance to the popularized image of the genus (with a longer crest, like P. walkeri) have been featured in the Land Before Time series, mostly as background characters or characters with one-liner apperances. Image:Para.jpg‎|A mother Parasaurolophus, with her young, in The Land Before Time IV: Journey through the Mists. Image:Headshot_2.jpg|Headshots of a Parasaurolophus (left) and a Lambeosaurus, in "The Amazing Threehorn Girl". Image:Ducky.jpg|Main character Ducky, in The Land Before Time. Image:Image;_Sequel_Ducky.jpg|Ducky, in The Land Before Time VII: The Stone of Cold Fire. Image:Mamma Swimmer.JPG|Mrs. Swimmer, Ducky's mother. References External links * Scientists Use Digital Paleontology to Produce Voice of Parasaurolophus Dinosaur; from Sandia National Laboratories. * [http://skeletaldrawing.com/psgallery/images/parasaurolophuscomparison.jpg Restorations of P. walkeri and P. cyrtocristatus], to the same scale, by Scott Hartman; at Skeletal Drawing.com. * ''Parasaurolophus page on Enchanted Learning.com Category:Dinosaurs Category:Hollowhorns Category:Swimmers